They were doubtlessly the animating principle of many hours that superficially seemed vacant.是什么意思？

They were doubtlessly the animating principle of many hours that superficially seemed vacant.

在表面看来无所事事的许多时刻中,它们无疑是活跃的因素.

they

pron. 他/她/它们，人们，大家，政府，当局，她们；

例句
The storms had abated by the time they rounded Cape Horn.
他们绕过合恩角时，暴风雨已经减弱。

were

be的过去时复数和第二人称单数形式，有时代替 was,用于条件从句、动词 wish 之后等；

例句
Shops, houses, and vehicles were set ablaze.
店铺、房子和车辆全都陷于火海。

doubtlessly

adj. 毫无疑问；

例句
It would doubtlessly do Bertha no harm.
这对伯莎肯定是无害的.

the

art. 指已提到的人（物），指说话人与听者已知的人（物），用于独一无二的事物前，与形容词最高级和序数词连用；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

animating

v. 使有生气( animate的现在分词 )，驱动，使栩栩如生地动作，赋予…以生命；

例句
The girls watched, little teasing smiles animating their faces.
女孩们注视着，脸上挂着调皮的微笑，显得愈加活泼。

principle

n. 原则，原理，准则，道义，道德标准，本能；

例句
Haig went on to elucidate his personal principle of war...
海格继续解释他个人的战争原则。

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

many

adj. 许多，多的；pron. （与复数动词连用）大多数人；

例句
There are many people who still find the act of abortion abhorrent.
仍有很多人对堕胎行为表示厌恶。

hours

n. 小时( hour的名词复数 )，固定时间，一小时的时间或行程，重要时刻；

例句
The workforce have recently been calling for their working hours to be reduced. Many companies have accordingly switched to a five-day week.
工人们最近一直在呼吁缩短工作时间。许多公司于是转成了一周五天工作制。

that

det. 那个，那；pron. 那个，那；conj. 多么，如此…以至，用于某些动词、形容词和名词后，引出各种从句；adv. 不那么，那样；

例句
...expensive make-up that we saw being advertised by a beautiful model...
我们所见的由一位漂亮模特代言的昂贵化妆品

superficially

adv. 浅薄地，干；

例句
He combined consummate shrewdness with the disposition superficially to fraternize.
他把高度的精明和温和敦厚的外表结合了起来.

seemed

v. 好像，仿佛( seem的过去式和过去分词 )；

例句
Steve seemed to acquiesce in the decision...
史蒂夫好像默认了这个决定。

vacant

adj. 空闲的，空缺的，空虚的，茫然的；

例句
A vacant lot or a bombsite can, to the amateur naturalist, produce an extraordinary variety of flora and fauna...
对于业余博物学者来说,在一片空地上或被炸后的废墟里可能发现种类繁多的植物群和动物群。